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Help to decode PCANView trace for Comm Stoppages

PostPosted: Thu 23. Aug 2018, 15:55
by DougPLC
I have almost no experience with CAN but have used PCANView 3.2 at someone else's direction.
Now my issue is on a different assembly machine using a Siemens S7-315 with ProfiBus to CAN bridge. The machine I/O is on CAN but we see a momentary communications freeze at random intervals - could be 15 secs to 3 minutes between freezes.
Can anyone help decode the attached trace file to help find the source of the error?
Also I see RTRs with ID 070A with no response. Is this a problem?
Any help would be appreciated.

Re: Help to decode PCANView trace for Comm Stoppages

PostPosted: Fri 24. Aug 2018, 08:29
by M.Maidhof
Hi,

it will be better to post the problem in a Siemens PLC forum, we don´t know that system and in the trace we don`t see any CAN errors.

regards

Michael

Re: Help to decode PCANView trace for Comm Stoppages

PostPosted: Mon 10. Sep 2018, 11:59
by DougPLC
Thanks for the recommendation but the folks on the Siemens forum don’t know anything about CAN bus.
How would electrical noise on the CAN bus show in a PCAN View trace?
If a station on the bus does not respond to an RTR what does that do to the performance of the bus?

Re: Help to decode PCANView trace for Comm Stoppages

PostPosted: Mon 10. Sep 2018, 12:35
by M.Maidhof
Hi,

EMC could produce errorframes. You will see them as errors in the trace, when you have enabled this option in the tracer.

About RTR: this is depending on how the software protocol on that bus handles such an problem. By default, nothing will happen.

regards

Michael